Important: VAERS reports alone cannot determine if a vaccine caused an adverse event. Reports may contain incomplete, inaccurate, or unverified information. Correlation does not equal causation.
The polio vaccine is one of the greatest public health achievements in history, virtually eliminating polio in the developed world. VAERS tracks adverse events for both the current inactivated vaccine (IPV) and the historical oral vaccine (OPV).
Important context: most IPV VAERS reports are from combination vaccines (like DTaP-IPV) where the polio component is given alongside other antigens. Side effects may be from the combination rather than the polio component specifically.
Common:
IPV is considered one of the safest vaccines. Serious adverse events directly attributable to IPV are extremely rare.
The oral polio vaccine (OPV) carried a very small risk of vaccine-associated paralytic polio (VAPP) — about 1 case per 2.4 million doses. This is why the U.S. switched exclusively to IPV in 2000. OPV is still used in some countries for its ability to provide intestinal immunity and stop wild poliovirus transmission.